Worm-drive crane



June l0, 1939 l E. H. LlcHTr-:NBERG 1,763,617

WORM l DR IVE CRANE Filed June 25, 1928 4 Sheets-Sheet 1 61H01 ne uw *June l0, 1930. I E. H. LlcHTNBl-:RG 1,763,617

WORM DRvE CRANE v A n @Het l @Emery kton ne ya June 10, 1930. E. H, LICHTENBERG WORM DRIVE CRANE Filed June 2'5. 1928 4 Sheets-Sheet 3 fltbomel June l0, 1930. E, H. LicHENBERG 1,763,617

WORM DR IVE CRANE Filed June 25. 1928 4 Sheets-Sheet 4 CII Patented June w, 1930 MNWW STATES PATENT GFFICE ERICH H. LICHTENBERG, OF MILWAUKEE, WISCONSIN, ASSIGNOR TO KOEHRING COM- IPANY, OF MILWAUKEE, WISCONSIN, A CORPORATION OF WISCONSIN WORM-DRIVE CRANE Application led June 25,

rlhis invention has to do with the art of excavating and material handling machines, and embodies novel improvements inthe type of such machines commonly called rotary cranes, wherein there are provided three general features of construction, namely, a suit-- able traction base, a crane or turn-table body mounted upon said base, and a boom and bucket excavating apparatus yassociated with the body for operation by machinery thereon.

This invention appertains directly to the machinery carried by the body ot' the crane, and comprising drum operating mechanism suitably motor driven, by which the boom and bucket actions ofthe machine are controlled.

Heretofore, the machinery upon a crane body has been unduly complicated including certa-in cable operating drums and extensive trains of gearing for the transmission of power to the drums from the motor,v and for conveying the power to the traction mechanism by which the machine is propelled.

My invention intends to roduce an improved operating drum unit for a crane,

wherein the necessity for using the side frames and extensive gearing such as employed today is obviated, though it is within the purview of my invention to employ the side frames if for some special reason they should be necessary.

By dispensing with side frames and eX- tensive trains of gearing, I am enabled to produce my boom and bucket operating mechanism at a greatly lowered cost, simplify the controls materially and otherwise generally cheapen the cost of production of the type of large machines to which my invention particularly relates.

In the carrying out of my invention, I utilize a worm gear unit which I think is wholly novel in its adaptation to the particular use to which I put it. The said worm gear unit is associated in a novel manner with the drum features that are required for the operation oi the boom and excavating devices ot cranes ot those types known as clam shell` dragline and shovel cranes. Moreover. in the construction oi inv drum operating wi gear mechanism, I utilize a very 1928. Serial N0. 288,159.

simple arrangement of drums, relatively few actuated spur gears, and very advantageous driving connections between the unit and the tract-ion operating means at the base of the crane,

Obviously, if I am able to do away with a large number of the ordinary gears required in crane operating machinery of the type 0f my invention and eliminate the employment of side frames and other parts which require the use of considerable precision machining work, the desired results hereinbefore outlined will be accomplished.

Ey the employment of the special type of worm gear unit which I have referred to as the operating'means for the drum mechanism and also the traction features, I am enabled to arrange the power unit or engine, usually a gas motor longitudinally of the cab or crane body.

This, in addition to the economy of spaceatforded by the said unit itself, enables all of the machinery in the car body to be assembled in a rather narrow compass, permits the cab or swing body to be constructed, narrower than heretofore, if desired, and if the said body is built as wide as heretofore, allows a great deal of space therein from which to enable access to the machinery in the han dling of the crane.

In the accompanying drawings, I illustrate a preferred form of machine embodying my invention, and the figures of the drawings may be briey described as follows Figure 1 is a side elevation of a crane showing the inventionv applied thereto.

Figure 2 is a view lshowing more particularly the crane body and traction base, and bringing out the arrangement of the drum loperating mechanism, driving connections leading to the traction or caterpillar driven parts, certain parts being broken away.

Figure 3 is a top plan view of the machine looking down on the swing or crane body and illustrating to some extent the simple form of the worm gear unit.

Figure is a vertical sectional view taken about on the line fl--fi of Figure Q.

Figure 5 is an enlarged view showing the main worm gear housing unit, parts broken away to illustrate the manner of entering the engine shaft into the said unit, and mounting thereon of the driven worin.

Figure 6 is a front View of the parts shown in Figure 5 particularly, the upper part of the worm gear housing being shown in section.

Figure 7 is a fragmentary sectional view bringing out more clearly the mounting and arrangement of the umbrella gear forming a part of the gear train for forming the traction base and for causing swinging of the swing body.

Figure 8 illustrates the brake means to be applied to stop swing of the body on the traction means, and

Figure Q is a perspective View of a bevel cupped' gear partly in section,'.which cooperates with the traction and swing mecha nism.

I now describe the general crane construction illustrated in Figure 1 as comprising the.

swing' body A, the traction base B, the shovel boom C, clipper handle D and dipper E. Esicepting for the operating drum mechanism and arrangement of the power plant and traction driving connections` my crane embodies dipper operating, crowding and racking in cable means 1; also' dipper hoisting cable means 2; and also cable raising means 3 for the boom @substantially like the corresponding features of Russell Letters Patent No. 1,639,752, issued August 23rd, 1927, and Russell Letters Patent No. 1,662.902, issued March 20th, 19:28, I do not think it necessary 'therefore to refer to 4these` particular features of my crane, as regards the boom and excavating devices since they may be very considerably modified within the purview of the invention and the construction illustrated is merely to exemplify the adaptation of my particular improvements. Moreover, of course. instead of the boom C and excavator D type of attachment shown in Figure 1, there may be substituted a suitable clam shell boom and clam shell bucket cable, apparatus, or there maybe used what is known as the dragline type of boom and bucket apparatus, these all being interchangeable, after a manner now known to those versed in the art.

I refer particularly now therefore to the features comprising my invention and .to Figures 2 and t of the drawings especially. In Figure 2 it will be observed that the power .unit which is a gasoline motor t is disposed longitudinally at the rear central portion of the crane body A and the said power unit has its power shaft extending forwardlv and suitably connected with the driving shaft 5 of my worm gear driving unit or mechanism.

There may be interposed between the engine 11 and` the shaft 5, suitable clutch -mechanismin the clutch housing` 6, but 'same is not illustrated as not material to the invention. The Worm gearing of my invention is arranged within a ear housing 7, see Figure 4, having at its le t and right sides, the offstanding journals 8 and 9 that perform a dual function as they constitute bearings in which are mounted the drum drive shaft 10, and also constitute supporting journal bearings upon which are disposed for rotation the drum 11 at the left and the drum 12 at the right. r1`he journal 9 is carried by a remoV- able side plate 13 forming a part or the right side of the housing 7. This plate 13 is removable and slightly cupped or recessed at the central portion of its outer surface to receive the inner flange of the drum 1Q. Similarly the housing 7 at its left side is re- `cessed or cupped to receive the inner flange of the drum 11. The provision of the cover or side plate 13 of the housing 7 enables access to the interior of the housing in the upper portion of which is mounted the driving worm gear 16 keyed to the shaft 10. The drums 11 and 12 are thus .afforded a loose mounting upon their trunnion or journal members 8 and 9. The drums 11. and 12 are equipped with outwardly projecting brake and clutch drum flanges designated 11"l and 12, clutch means heilig provided to cooperate for connecting the parts 11a and 1Qa with the shaft 10 to rotate therewith, at will. The' braking .means is employed of course, to hold the drums stationary, when the cable means wound around said drums requires such operation, in the usual well known manner.

When the worm gear unit now being described, is employed for a shovel crane, the drum l1 will be revcrsibly operable, and will have the cable means to wind thereabout, so that crowding and racking in operations of the dipper E may be performed. Under such conditions. the drum l2 will be used to operate the cable means for hoisting the dippcr E.

-When my machine is uscd for clam shell purposes one of said drums will be en'iploycd for the hoisting line of the clam shell and the other for the closing line, but the reversible operation of the drum 11 is not necessary to be employed.

Again, when my machine is use/,l for dragline purposes, one of the said drums ll and 12, will be employed for the hoisting linc of the drag bucket, and the other will be employed for the dragline also: similarly. to the clam shell operation, under such conditions, no reversal of operation of the drum 11 will be necessary as the same is only employed for power shovel purposes. The worm gear 1G is the main drum mechanism operating gear and is directly engaged with the worm 17 on the driving shaft 5 operated from the engine shaft under suitable control. Below the worm 17 is disposed a secondary worm gear mechanism comprising the worm gear 18 adapted to function under some conditions as a driving 'means for causing the reverse operation of the drum 11 in a shovel crane;

rformation of the upper portion of the casing being carried by a side or cover plate 21 removable from the main housing 7 to enable access to the interior of said housing at its lower portion. A ltract-ion andswing shaft is mounted in the lower portion of the housing 7 supported by the journals 19 and 19a as bearings therefor, and the worm gear 18 is keyed to this shaft. The worm gears 1.6 and 18 are therefore driven in opposite `directions.

At its lower end portion, the gear housing 7 is formed with outwardly projecting arms i 7a and 7b provided with bearings for the shaft 22 and said shaft 22 therefore consti- ,tutes an anchoring means connecting the housing 7 with the vertical short standards 23 of the base casting.

At its central lower extreme portion, the housing 7 is formed with arecess providing a bearing 26 for the upper trunnion 27 of the cupped bevel-gear 28, seen best in Figures 4 and. 9. This cu ped bevel-gear is equipped with a downwardly projecting or lower trunnion 29 which is received in a bearing 30 in the central lowest portion of the base casting 24.

It will be understood, of course, that antifriction rollers' or other bearings may be provided in the bearing cavities or parts 26 and 30 in accordance with the best provisions of machine designing, but these are not material to the invention and such bearings will not again be referred to.

,The function of the worm gear 18 as a reversing drive means for the drum 11, will now be set forth. On the shaft 20 is keyed a pinion 31 alongside the worm gear 18 and meshing with a similar pinion 32 above it and carried by the counter shaft 33, see Figure 4. The counter shaft 33 is supported in a hollow journal member 34 ofstanding from the left of the housing 7 about centrally between its upper and lower ends, and carries a driven gear 35 which meshes in turn with alarger gear 36 carried by the drum 11 in any suitable manner. The gear 35 is indirectly supported by the shaft 33, and is shiftable slightly from its full line position of Figure 4to its dotted line position of said ligure. In the latter position the gear 35 may enter and directly 1nterlock with a toothed gear recess of the boom hoist drum 37 about which may wind the cable 37', see Figure 1, by which the boom C may be raised or lowered and held in desired adjusted positions within the range of such movement. The drum 37 is journaled I upon the hollow journal member or trunnion 34 in which the shaft 33 is mounted. I have not illustrated any shifting means for the gear 35 but various kinds of such-means may be resorted to. For instance, the gear may have a grooved hub and a shift lever or rod may be engaged by a shifting yoke with said hub to thereby enable movement of the gear inwards or outwards in relation to the drum 37.

Obviously, by reason of the train of gears and pinions 31, 32, 35 and 36, thedrum 11 may be driven in a direction reversely to that in which it will be driven when the clutch means coacting with the clutch and brake drum 11a are used to connect said drum 11 with the shaft 10. On the' shaft 33 is arranged a clutch and brake'drum 33 having a hub portion keyed to the shaft 33 and on which the gear 35 is splned to shift in the manner above stated. The use of the clutch means associated with the drum 33 may, of course, enable the gear 35 to be connected with the shaft 33 and driven thereby or not, as'may be desired. Brake means cooperating with the drum 33El will enable the holding of the boom hoist cable 37 at any adjustment of the boom desired when the gear 35 is in cooperation with the drum 37.

The portion ofthe housing 7 opposite the drum 37 is in the form of a cover or side plate removably applied to the body of the housing and through which access may be had to the interior of the housing from the left side thereof as viewed in Figure 4.

Passing now to the function of the worm ear 18 in its cooperation with the traction eatures, and the swing gear features of my invention, I note, as will be seen'in Figures 2 and 4, that the cupped bevel-gear 28 has its teeth engaging opposite bevel-gears 39 and 40 on the shaft 20. At the inner sides of tlese Y bevel-gears 39 and 40, are cap glands 41, the purpose of which is to prevent the escape of lubricant received in the housing 7. In other words, the housing 7 will be supplied with a lubricant so that the gearing enclosed thereby will be free running in oil all the time, the cap glands 41 coacting to close the outer ends of the journals or trunnion members 19 and 19a.

Similarly, cap glands 14 and 15 are provided to coact with the outer ends of the jour.

traction base I3, and is adapted to drive said shaft and the bevel-gear at the lower end thereof. Said bevel-gear 45 meshes with a similar gear 46, see Figure 4, on the traction shaft 4T, and is therefore adapted to drive said traction shaft. The traction shaft 47 and the driving connections therebetween, and the endless traction members 4S form features of an invention other than my own and it suiiices to state that there are employed com bination clutch and brake sets 49 cooperative with the shaft 4T and connected with chain driving sprockets 50 having the sprocket Vchains 51 leading to the traction belt drive sprockets 52. Fower may be transmitted from the shaft 47 through the combination clutch and brake sets 4S) to the sprockets 50, and thereby to the traction belts 48 to drive either or both of these belts at will. Or again, either or both of the traction belts may be braked to hold either or both, more or less stationary, for controlling steering actions. lVhen the brakes are applied to both of the clutch and brake sets 4t). the gear 4G will become locked, and will lock the center pin shaft 44 and the umbrella gear 43 keyed thereto. Under these conditions, it will be apparent that if the swing and traction gear 42, see Figure 2, is operated in either direction by the cupped bevel-gear 28, the said gear 42 will travel around the gear 43 and swing the crane body in the customary well known manner along with its boom and excavating apparatus.

For the purpose just last described therefore, I provide on the shaft 20,*the clutch drums 52 for clutching either ofithe bevel-gears 39 and 40 to the shaft 20 driven by the worm gear 18 and depending upon which one of these bevel-gears is rendered operative, the cupped gear 28 will be operated in one of opposite directions and thereby correspondingly actuate the spur gear 42 which travels around the umbrella gear 43 when said umbrella gear is held stationary.

Of course, when the umbrella gear 43 is not held stationary, it is in fact, a traction drive gear when driven in either direction by the swing and traction gear 42 and there will he no turning of the body A of the crane.

lVhen the gears 42 and 43 are employed for swinging the body of the crane, I must necessarily provide some. means for stopping the swin; r movement when the boom C and excavating apparatus carried thereby have been swung tothe desired position, supplying those for dischaige or for digging. To this end.y l provide. as .sr-en in Figure 4 and the detail view of Figure S, a brake control consisting of a brake band 53 which encircles a brake surface at the uppermost portion of the traction frame casting 54. rIhe said brake hand 5S has one end dead-ended or attached to an arm 55 on the base casting 24 of the body A. The other end of the brake band, its live end, is connected with one arm of a bell crank lever 56 also mounted on said base casting 24. This bell crank lever 56 is operable by a foot piece or tread member 57 that when depressed, will apply the brake band to the brake surface of the casting 54, and in this way as the crane body A is swung under the influence of traveling action of the gear 42 around the gear 43, said body may be stopped at any suitable point in its movement by mere depression of the foot piece 57 by the operator.

It is notable in regard to the traction frame casting 54 that it is somewhat peculiarly constructed in that a central bod portlon is equipped with integral oli'standing arms 58 and these arms are formed with the longitudinal traction belt supporting frames 59 integral therewith. The traction belts 48 may be mounted upon the frames 59 in quite the usual manner but the unique feature of construction that I refer to is the employment of a single traction base vframe having a central body portion and integral traction belt frames at its opposite sides, the whole a. single unit. The arms 58 may be provided with openings for passage of the sprocket driving chains 51, as seen best in Figure 1.

It is noted that the operating means for the combined clutch and brake sets/.t9 as has heretofore been proposed includes certain control rods and parts including rods or shafts leading down through the hollow center pin shaft 44, same not being illustrated in detail in this application in view of the fact that the traction driving means and the control of the lower crane machinery therein constitutes an invention separate from the one embodied in this case.

A noteworthy feature lies in the instrumentalities for operating the brakes, that is, the steering brakes which are availed of for the traction lock as well as the steering means, thereby eliminating parts and complexity of construction. Pivotally mounted between their ends of the turntable of the crane are two control levers G0 and 61. .Extending down through the center pin on the axis of rotation are two tubular members 62 and 63 which are arranged concentrically one within the other, the ends of these tubular members being affixed to the levers (i0 and 61 which are mounted so that operation thereof causes upward or downward movement of the tubes G2 and 63. The lever 61 has an operative connection with the swing brake so that operation thereof causes operation of the latter. Through the pipe G53 and bell crank (S4 the operatmg mem ier 61 is operatively connected with the steering brakes in the 'following manner. The shaft 65 is included in the traction construction of the machine and keyed thereto is a yoke 66 which is designed for shifting the jaw clutch. A crank 67 is I splined to the other end of the shaft 65 and is connected with the instrumentalities associated with the operating lever through the medium of the link shown at 68. The bell crank 69 is pivotally mounted on the shaft and has a ingcr for operating the brake 49, the other arm of the. bell crank abutting against the sidev of the arm 67 to which the link 68 is connected. This abutting relationship allows the bell crank 69 to rotate counter-clockwise without entailing rotation of the shaft 65 when motion is imparted from the lever 61, but when the lever 60 is operated, parts 69, 67, and 66 must move as a unit. A spring is included in the construction which constantly tends to hold the bell crank 69 in its a'butted relation with respect to the cranlr67. The remainder of the brake construction together with its operating instrumentalities is of the Well known type, the operation of which will be appar ent from the drawings. In operating the crane if the lever 60 is lifted. the clutch at the left side ofthe machine will be released and i the brake set, while if this lever is depressed beyond its natural position, the clutch on the right side will be released and the brake set. However, upon operation of the lever 61 in an upward direction, t-heV swing brake will be applied throwing the machine into tractive operation. Depression of the lever 61 causes a release of the swing brake and a setting of both of the steering brakes.

General rsum of construction and operation The dru'm 12 is the dipper hoist drum operating the cable 2. The drum 11 is the crowding out and racking in means operating the cable 1 in conjunction with the crowding and racking pinion 1a on the boom. The main worm gear at 16 is driven from the worm shaft 5 by the worm 17 to therebyturn the shaft 10 and operate either one of the drums 11 and 12 or both of them,vdependent upon the clutching of these drums to the shaft 10. In this way, the drum 11 may be turned in one direction as for crowding out the dipper Il, To turn it in the opposite direction for racking in the clipper, the drum 11 may be reversely operated by the drive from the worm shaft 5, worm 17, worm gear 18, spur gears 31 and 32, shaft 33, spur gears 35 and 36, the. latter atiixed to the drum 11 in some substantial way.

For operating the boom4 hoist drum 37, the drive is taken from the Worm 17, worm gear '18. spur gears 31 and 32, shaft 33, boom hoist clutch 33 i and gear 35, the latter .adjusted so as to enter the toothed gear recess in the left end of the drum 37.

For swinging the body A of the crane in either direction, one of the clutch means 51 and 52?.,is' iavailed of to connect the shaft 20 to rotateia certain one of the bevel pinions or gears 39 and 40. The operative pinion turns the cupped gear 28, its connected gear 42, and the gear 42 travels around the umbrella gear 43 which has previously been locked from movement by locking the traction shaft 47 through the application of both brakes of the brake and clutch sets 49.

Stoppage of the swinging of the body A is e li'ected by the brake band 53 operated by the foot'piece 57, or by reverse clutch.

To transmit driving operation to the traction devices 48, the brake band 53 may be used to hold the body A stationary in respect to the traction base. The drive may then be taken otf through the clutch devices 51a and 52a operating the cupped gear 28 and its pinion 42 in either of opposite directions, for forward driving of the traction members 48 or rearward driving as required. Turning of the swing and traction gear 42 will rotate the umbrella gear 43, turn the center pin shaft 44 and transmit motion to the traction shaft 47 through the gears 45 and 46. The motion of the shaft 47 may be transmitted to either or both of the traction members 48 by the combined clutch and brake sets 49. Having thus described my invention, what I claim as new and desire tosecure by Letters Patent of the United States, is

' 1. In acrane, in combination, abase,a crane body thereon, excavating means carried by the crane body, and operating machinery on the crane body for the excavating means, comprising an engine on the body, a Worm shaft and worm being directly connected t0 said engine, drum mechanism for the excavating means, and driving connections between the worm aforesaid and said drum mechanism.

2. In a crane,'in combination, a base, a crane body thereon, excavating means carried by the crane body, and operating machinery on the crane body for the excavating vmeans, comprising an engine on the body, a

worm shaft and worm driven from said engine, drum mechanism for the excavating means', and driving connections between the worm aforesaid and said drum mechanism, a housing for the Worm and worm shaft and rigidly mounted on the crane body, a Worm gear operable from said Worm and arranged in said housing, and operating drums for the drum mechanism and mounted on said housing and arranged to be driven by said worm gear.

3. In a crane, 1n combination, a base, a crane body thereon, excavating means carried by the crane body, and operating machinery on the crane body for the excavating means, comprising an engine on the body, al

worm shaft and Worm driven from said engine, drum mechanism for the excavating means, and driving connections between the worm aforesaid and said drum mechanism, a housing for the worm and Worm shaft rigidly 'mounted on the crane body, a worm gear operable from said worm and arr: nged in said housing, and operating drums for the drum mechanism and mounted on said housing and arranged 'to be driven by said worm gear, the said drums being disposed at opposite sides of the housing for the reception of cable means and supported by the housing.

d. iin a crane, in combination, a base, a crane body thereon, excavating means carried by the crane body, and operating machinery on the crane body for the excavating means, comprising an engine on the body, a Worm shaft and vvorm driven from said engine, drum mechanism for the excavating means, and driving connections between the Worm aforesaid and said drum mechanism, a housing for the Worm and Worm shaft rigidly mounted on the crane body, a Worm gear operable from said Worm and arranged in said housing, and operating drums for the drum mechanism and mounted on said housing and arranged to be driven by said Worm gear, the said drums being disposed at opposite sides of the housing for'the reception of cable means and supported by the housing, a shaft With which the said Worm gear is connected, and clutch means for clutching said shaft to each one of the drums for driving said drums in one direction.

5. In a crane, in combination, a base, a crane body thereon, excavating means carried by the crane body, and operating machinery on the crane body for the excavating means, comprising an engine on the body, a Worm shaft and Worm driven from said engine, drum mechanism for the excavating means, and driving connections betvveen the worm aforesaid and said drum mechanism, a housing for the Worm and Worm shaft rigidly mounted on the crane body, a Worm gear operable from said Worm and arranged in said housing, and operating drums for the drum mechanism and mounted on said housing and arranged to be driven by said Worm gear, the said drums being disposed at opposite sides of the housing or the reception of cable means and supported by the housing, a shaft Tvith which the said Worm gear is connected, and clutch means for clutching said shaft 'to each one of the drums for driving said drums in one direction, and means operable from the Worm shaft for actuating one of the said drums in a direction reverse to that previously referred to.

6. ln a crane ofthe class described, a crane body having operating mechanism for eX- cavating machinery comprising an engine disposed with its driving shaft lengthwise of the body, drivingl means comprising a housing for Worm g ins: disposed on said body, a Worm shaft drivably connected to said engine and entering :iid housingr and having a 'Worm thereon, a iin Worm gear operable from said 'Worm and mounted in the housing, cable drums for operating an excavating device and mounted on said housing, means actuated by said Worm gear to turn said drums in one direction, and secondary gearing driven by said Worm for turning one of said cable drums in a reverse direction.

7. In a crane of the class described, a crane body having operating mechanism for excavating machinery comprising an engine disposed With its driving shaft lengthwise of the body, driving means comprising a housing for Worm gearing disposed on said body, a Worm shaft drivably connected to said engine and entering said housing and having a Worm thereon, a main Worm gear operable from said Worm and mounted in the housing, cable drums for operating an excavating device and mounted on said housing, means actuated by said Worm gear to turn said drums in one direction, and secondary gearing driven by said Worm for turning one of said cable drums in a reverse direction, a base for lthe crane body and traction means therefor, and driving connections between the secondary gearing and said traction means.

8. In a crane of the class described, a crane body having operating mechanism for excavating machinery comprising an engine disposed with its driving shaft lengthwise of thebody, driving means comprising a housing for worm gearing disposed on said body, a worm shaft drivably connected to said engine and entering said housing and having a Worm thereon, a main Worm gear operable from said Worm and mounted in the housing, cable drums for operating an excavating dc vice and mounted on saidhousing. means actuated by said Worm gear to turn lsaid drums 1n one directiomand secondary gearing driven by said worm for turning' one of said cable drums in a reverse direction, a base for the crane body and ltraction means therefor, and driving connections between the secondary gearing and said traction means. including a swing and traction gear` a driving gear attached to the swing and traction gear, and means for communicating reverse movements to saidv driving gear from said secondary gearmg.

9. ln a crane, in combination, a base, a body mounted thereon, an excavating device carried by the body and operating means for the excavating device includinfy an engine disposed longitudinally of the iody at the central portion thereof, a shaft and Worm drivably connected to said engine, a Worin gear unit comprising a housing at the central portion of `the body in alignment with 'the engine and receiving said shaft and Worm, a Worm gear operable from said worm, and drum mechanism in operative connection with said Worm gear.

l0. In a crane, in combination, a base, a body mounted thereon, an excavating device carried by the body and operating means for the excavating device including an engine disposed longitudinally of the body at the central portion thereof, a shaft and Worm ldrivaloly connected to said engine, a Worin gear unit comprising a housing at the central portion of the body in alignment with the engine and receiving said shaft and Worm, a Worm gear operable from said Worm, and drum mechanism in operative connection with said Worm gear, and including spaced separate drums independently rotatable upon the said housing at opposite sides thereof, and cable means received by said drums and connected with the excavating device aforesaid.

11. In a crane, in combination, a base, a body mounted thereon, an excavating device carried by the body ap d operating means for the excavatin device, including an engine disposed longitudinally of the body at lthe central portion thereof, a shaft and Worm drivably connected to said engine, a Worm gear unit comprising a housing at` the central portion of the body in alignment. with the engine and receiving said shaft and Worm, a main Worm gear operable from said Worm, and drum mechanism in operative connection with said worm gear, and including spaced separatedrums independently rotatable, uponthe .said housing at opposite sides thereof, cable means received by said drums and connected with the excavating device aforesaid, means to operatively connect said drums to the main Worm gearaforesaid to turn the drums in one direction, and Secondary gearing operable from the Worm sliaft for turning one of said drums in an opposite direction.

12. In a crane, in combination, a base, a body mounted thereon, an excavating device carried by the body and operating means for the excavating device, including an engine disposed longitudinally of the body at the central portion thereof, a shaft and Worm drivably connected to said engine, a worm gear unit comprisingv a housing at the central portion of the body in alignment with the engine and receiving said shaft and worm, a main Worm gear operable from said Worm, and drum mechanism in operative connection., with said worm gear, and including spaced separate drums independently rotatable upon.V

the said housing at opposite 'sides thereof,

cable means received by said drums and connected with the excavating device aforesaid, means to operatively connect said drums to the main Worm gear aforesaid 'to turn the drums in' one direction, and secondary 'gearing operable from the Worm shaft for turning one of said drums in an opposite direction, said secondary gearing including a secondary Worm gear in a ignment with the main worm gear and the worin Shaft, and a train of gears intermediate the secondary Worm gear and the reversible one of the drums aforesaid.

13. In a crane, in'combination, a base, a

body mounted thereon, an excavating device carried by the body and operating means for the excavating device, includin an engine disposed longitudinally of the ody at the central portion thereof, a shaft and .Worm drivably connectedl to said engine, a worm gear unit comprising a housing at the central portion of the body'in alignment With the engine and receiving said shaft and Worm, a main Worm gear operable from said Worm, and drum mechanism in operative connection With said Worm gear, and including spaced separate druinsindependently rotatable upon the said housing at opposite sides thereof, cable means received by said drums and connected with the excavating device aforesaid, means to operatively connect said drums to the main Worm gear aforesaid to turn the drums in one direction, and secondary gearing operable frointhe Worm shaft for turn- .ing one of said drums in an opposite direction, and a swing and traction gear operably connected with the secondary gearing aforesaid.

14. In a crane, in combination, a base, a body mounted thereon, an excavating device carried by the body and operating means for the excavating device,. including an engine disposed longitudinally of the body at the central portion thereof, a shaft and Worm --drivably connected to said engine, a Worm gear unit comprising a housingv at the central portion of the body in alignment With the engine and receiving said shaft and Worm, a main Worm gear operable from said worm, and drum mechanism in operative connection with said Worm,4 gear, and including 'spaced separate drums independently rotatable upon the saidhousing at opposite sides thereof, cable means received by said drums and connected with the excavating device aforesaid, means to operatively connect said drums to the main Worm gear aforesaid to turn the drums in one direction, and secondary gearing operable from the Worin shaft for turning one of said drums in an opposite direction, said secondarv gearing including a .secondary worm gear in alignment with the main Worm gear and the Worm shaft, and a train of gears intermediate the secondary Worm gear andthe reversible one of the drums aforesaid, a 4swing and traction gear adjacent to the secondary gearing aforesaid, and means for communicating reverse movements to said swing and traction gear from' the secondary gearing.

15. In a crane, in combination, a base, a body mounted thereon, an excavating device carried by the body and operating means for.

the excavating device, including an engine disposed longitudinally of the body at the central portion thereof, a shaft and Worm drivably connected to said engine, a Worm gear unit comprising a housing at the central portion of the body in alignment with the drufn 11 in a direction reverse to that in -which the drum 11 will be driven directly from the shaft 5.

21. In a crane, operating machinery as de.

scribed including the worm gear housing 7, the anchorage means 7, (b'for said housing arranged at the base thereof, the independently rotatable drums 11 and 12 mounted upon the housing, the worm gears 16 and 18, the worm shaft drive means therefor including the parts 17 and 5, means for driving the drums 11 and 12 from the gear 16, and other means for driving1 the drum 11 from the worm gear 18 in a irection opposite to that in which it is driven by the worm gear 16.

In testimony whereof I adx my signature.

ERICH H. LICHTENBERG. 

